About Pulmonary Hypertension

Pulmonary hypertension (PH) is a rare but very complex and serious lung disease that is progressive and potentially fatal. PH is defined by high blood pressure in the lungs resulting from inflammation or scarring in the pulmonary arteries. If left untreated, PH can lead to enlargement and weakness of the right-side of the heart, a serious type of heart failure. 

  • PH is characterized by the presence of high blood pressure in the lungs.
  • PH can lead to right-sided heart failure.
  • PH can strike people of all backgrounds, ages, and genders.
  • PH affects between 5,000 and 10,000 Canadians.

Types of Pulmonary Hypertension

Pulmonary arterial hypertension (PAH)

WHO Group I

  • Idiopathic
  • Associated conditions
    (e.g. scleroderma)
  • Genetic

PAH is a disease in which blood is not able to circulate normally in the lungs due to narrowing of the arteries. This results in increased blood pressure in the lungs, causing the heart to work harder to pump blood into the lungs.

The heart can become enlarged, leading to right-sided heart failure and even death.

Chronic thromboembolic pulmonary hypertension (CTEPH)

WHO Group IV

CTEPH is caused by blood clots that do not entirely dissolve following pulmonary embolism, leading to the formation of scars within the pulmonary arteries that impede blood ow into the lungs.

After pulmonary embolism, up to 4% of patients may develop CTEPH within 2 years.

PH associated with left-sided heart disease

WHO Group II

  • Left-sided congestive heart failure
  • Mitral valve disease

PH associated with lung disease


  • COPD
  • Pulmonary fibrosis
  • Sleep apnea

PH caused by various other diseases

WHO Group V

  • Chronic renal failure
  • Vasculitis
  • Sarcoidosis

Sometimes It's PH

Additional Resources

Information Sheet for Medical Professionals
Download Resource 

PH Clinical Directory
Access Resource

Clinical Practice Guidelines
Access Resource 

The Impact of PH on Canadians
Access Resource 


Comprehensive information on pulmonary hypertension for medical professionals.